Field of the Invention
This invention relates to unit dose detergent compositions comprising a water-soluble container formed from a water-soluble film material enclosing a liquid composition with a relatively high water content.
Background Art
Unit dose detergent products are often found by consumers to be preferable for use in automatic dishwashing and clothes washing applications. Such unit dose products have several advantages, including convenience of use and dispensing, lower cost per use, and avoiding or minimizing skin contact with potentially irritating cleaning compositions.
Unit dose systems that can be used in aqueous liquid detergent or cleaning compositions are known in the art. For example, U.S. Pat. No. 4,973,416 (the '416 patent) discloses unit dose liquid detergent compositions enclosed within a water-soluble polymeric film pouch, where the liquid compositions are concentrated and contain a substantially all-organic neutralization system. Although stating that water can be in an amount less than about 24 wt % of the liquid composition, the '416 patent indicates that a preferred amount is 18 wt %. Furthermore, the only example of unit dose liquid detergent disclosed in the '416 patent has a liquid detergent composition with a total water content of 16.29 wt %. The disclosure of the '416 patent is incorporated by reference herein.
U.S. Pat. No. 6,037,319 (the '319 patent) discloses water-soluble packets containing concentrated liquid cleaning compositions which contain less than about 10 wt % water. The '319 patent at column 3, lines 42-44 points out that “[i]t is preferred to limit the amount of water in the liquid cleaning concentrate to less than 10 wt. % of the composition.” The disclosure of the '319 patent is incorporated by reference herein.
In addition, U.S. Pat. No. 7,563,757 (the '757 patent) discloses water soluble pouches containing liquid detergent compositions which contain a plasticizer, a viscosity modifier, and a relatively low level of water. The liquid compositions in the '757 patent contains less than 25 wt % water, and preferably between 5-15 wt % water, as indicated in column 2, lines 53-55. The disclosure of the '757 patent is incorporated by reference herein.
One limitation of these known unit dose detergent compositions is that the water content of the liquid detergent compositions is limited to a relatively low level to prevent the water-soluble film from being dissolved pre-maturely by the enclosed liquid detergent composition. Water is an inexpensive ingredient of the liquid detergent compositions and a ubiquitous solvent. There still remains a need for unit dose detergent compositions having a relatively high water content, which would reduce the cost of goods while increasing formulation flexibility of the unit dose detergent compositions.